final endodontic irrigation with ethanol

final endodotic irrigation with 70 percent ethanol enhanced calcium hydroxide removal from the apical third

1. FinalEndodonticIrrigationWith
70%EthanolEnhancedCalcium
HydroxideRemoval FromThe
ApicalThird
JOURNAL OF ENDODONTICS
Presented by:-
Dr. Abdul kadir

2. CONTENTS
•AIM
•INTRODUCTION
•SAMPLE PREPRARATION
•IRRIGATION PROTOCOLS
•CONFOCAL LASER SCANNING MICROSCOPE ANALYSIS
•STATISTICAL ANALYSIS
•RESULTS
• DISCUSSION
•CONCLUSION
•REFERENCES

3. Aim
The purpose of this study was to evaluate the cleanliness of root canal walls and
dentinal tubules using confocal laser microscopic analysis after attempting to
remove the calcium hydroxide dressing with different irrigant solutions and the use
of nonactivated irrigation or passive ultrasonic Irrigation (PUI).

4. Introduction
•Calcium hydroxide pastes are one of the most commonly used intracanal dressings
because of their antimicrobial properties and biocompatibility.
•Remnants of calcium hydroxide on the canal walls could influence the leakage of
root canal filling over time because of calcium hydroxide dimensional instability
and solubility.
•Residual calcium hydroxide also affects some sealers’ physical properties as well as
the penetration into the dentinal tubules, the sealers’ bond strength to root dentin ,
and even the filling of lateral canals.

5. •Mechanical instrumentation of the root canal with the master apical file at the
working length in combination with copious irrigation with NaoCl and EDTA is one
of the most frequently described methods for removing intracanal calcium
hydroxide.
•However, it has been reported that the removal of calcium hydroxide from the root
canal is difficult and remains a challenge in endodontic therapies because no
currently available strategy can completely and predictably remove calcium
hydroxide dressing before root canal filling.

6. Sample Preparation

7. The crowns of the teeth were sectioned at 15 mm from the apex to standardize the length of the roots
The working length was determined
Root canals were instrumented using ProTaper Universal Rotary instruments up to the F3 file
Irrigation was performed with 2 mL 2.5% NaOCl using a 5-mL plastic syringe and a 30-G irrigation
needle inserted passively into the canal at 3 mm from the apical foramen
After instrumentation, each root canal was flushed with 2 mL 17% EDTA for 1 minute; this was
repeated 3 times
Root canals were dried with F3 paper points

8. The samples were filled with calcium hydroxide powder mixed with propylene glycol and
0.1% rhodamine B dye
Two radiographs (mesiodistal and buccopalatal direction) were taken to confirm complete
filling of the canals with the calcium hydroxide paste
The specimens were stored in 37 C at 100%
humidity for 7 days

9. Irrigation protocols
•After this period, 2 coats of colored nail polish were applied to the specimens,
including the apical foramen, to prevent leakage of the irrigant.
•All specimens were also fixed in tubes containing silicon impression material.
•The coronal access was opened, and the intracanal dressing was initially removed
with 10 ml saline solution and instrumentation with the master apical file (f3) up to
the working length.

10. •Samples were randomly assigned into the following 8 experimental groups (n = 10)
according to the solution and method of irrigation:

A. I) Naocl/NAI: 6 ml 2.5% naocl * 3 minutes
II) Naocl/PUI: 6 ml 2.5% naocl divided into 3 applications of 2 ml ultrasonically activated each
time * 1 minute
B. I) EDTA-T/NAI: 6 ml 17% EDTA-T * 3 minutes
II) EDTA-T/PUI: 6 ml 17% EDTA-T divided into 3 applications of 2 ml ultrasonically activated each
time * 1 minute
C. I) Phosphoric acid/NAI: 6 ml 37% phosphoric acid * 1 minute 30 seconds
II) Phosphoric acid/PUI: 6 ml 37% phosphoric acid divided into 3 applications of 2 ml ultrasonically
activated each time * 30 seconds
D. I) Ethanol/NAI: 6 ml 70% ethanol * 3 minutes
II) Ethanol/PUI: 6 ml 70% ethanol divided into 3 applications of 2 ml ultrasonically activated each
time * 1 minute

11. •A final flush with 5 ml saline solution was performed for all groups.

12. Confocal laser scanning microscopic analysis
•The specimens were then sectioned with a diamond disk in low rotation at 1 and 4
mm from the apex.
•Slices were taken for confocal laser scanning microscopy with the wavelength of
absorption and fluorescence emission of 540/ 590 nm for evidence of rhodamine
b.
•The image samples were acquired 10 mm below the surface sample with 10x
magnification to a size of 1024 x 1024 pixels.

13. •The percentage of clean root canal walls and the depth of clean dentinal tubules were
measured with images of confocal laser scanning microscopy.
•The method proposed by moon et al to calculate the percentage of sealer penetration
into dentinal tubules was adapted to measure the percentage of clean root canal walls.
• First, in each sample, the total perimeter of the root canal was measured with the
software measuring tool.
•Then, the perimeter along the root canal walls where there was no evidence of residual
calcium hydroxide was measured. The percentage of clean root canal walls were then
calculated.

14. •The percentage of clean root canal walls and the depth of clean dentinal tubules were
measured with images of confocal laser scanning microscopy.
(A ) The selected perimeter of the root canal where there was no calcium hydroxide inside the dentinal tubules. (B ) The depth of
cleanliness inside the dentinal tubules at 4 standardized points.

15. Statistical analysis
•The authors performed the statistical analysis using SPSS statistics 25.0 software
(version 25.0; IBM corp, armonk, NY) and verified the normal distribution of the
data using the shapirowilk test.
•To assess the influence of the irrigating solutions and the methods of irrigation, 2-
way analysis of variance with the post hoc bonferroni test was used with the
values of depth of dentinal tubule cleanliness.
• Because of high heterogeneity among group variances, the clean perimeter
analysis was performed with the kruskal-wallis test followed by the post hoc test.
The testing was performed at the 95% level of confidence (P < .05).

16. Results
•None of the experimental protocols totally removed the intracanal medicament of
calcium hydroxide.
•Regarding the irrigation methods (NAI and PUI), no differences were found in
any of the tested solutions (2.5% NaoCl, 17% EDTA-T, 37% phosphoric acid, and
70% ethanol) (P < .05).
•Regarding the irrigation solutions, 70% ethanol presented a significantly higher
percentage of clean root canal walls compared with irrigation with 2.5% NaoCl
and 17% EDTA-T in both methods of irrigation (NAI and PUI, p < .05) (fig. 2A
and B).

17. •Similarly, a higher depth of cleanliness was observed after irrigation with 70%
ethanol compared with 2.5% NaOCl and 17% EDTA-T in both methods of
irrigation (NAI and PUI, P < .05) (Fig. 2).
• For both outcomes, no differences were observed between 70% ethanol and 37%
phosphoric acid (P > .05) or among 37% phosphoric acid, 2.5% NaOCl, and 17%
EDTA-T (P >.05).
•Representative images of each group can be observed in Figure 3A–H.

18. Representative confocal laser scanning microscopic images (20x magnification) of the apical root third of specimens irrigated by NAI with
(A ) 2.5% NaOCl, (B ) 17% EDTA-T, (C ) 37% phosphoric acid, and (D ) 70% ethanol and PUI with (E ) 2.5% NaOCl, (F ) 17% EDTA-T,
(G ) 37% phosphoric acid, and (H ) 70% ethanol.

19. Discussion
•Different irrigating solutions, such as saline, naocl, EDTA, citric acid, and
phosphoric acid along with combinations, have been used to remove calcium
hydroxide dressings.
•The authors observed significantly lower values of residual calcium hydroxide after
irrigation with the combination of EDTA-T and phosphoric acid compared with
naocl. However, most of the Specimens from the apical third still presented high
values of calcium hydroxide remnants.

20. •Therefore, the apical third was analyzed in the present study.
•The first results of the present study indicated that none of the irrigating solutions
could guarantee a total removal of calcium hydroxide dressing regardless of using
either NAI or PUI, with an average of 55.38% and 60.05%, respectively, of the root
canal walls still covered by calcium hydroxide dressing. However, the irrigation
with 70% ethanol was significantly more effective than 2.5% naocl and 17%
EDTA-T in calcium hydroxide removal.
•Recent studies demonstrated that 70% ethanol did not alter the inorganic content of
dentin after calcium hydroxide removal

but did increase the surface-free energy of
root canal dentin, significantly improving the wettability of the root canal sealer

21. •In this study, there were no differences between NAI and PUI in the apical third for
any tested irrigant.
•The study found that calcium hydroxide remnants significantly decreased the depth
of penetration of sealers and the percentage of sealer that penetrated into the dentinal
tubules.
•Additionally, the average residual volume at the apical region was 6.4% after several
protocols to remove intracanal dressings.
•The ideal method to remove intracanal dressings should involve an improved
irrigation technique, which allows a higher penetration of irrigating solutions into the
dentinal tubules.

22. Conclusion
•The present study demonstrated that 70% ethanol enhanced calcium hydroxide
removal from the apical root third compared with 2.5% NaoCl or 17% EDTA-T.
•Irrigation with 37% phosphoric acid showed comparable calcium hydroxide
removal in all of the tested groups.
•However, passive ultrasonic irrigation did not enhance calcium hydroxide removal
compared with NAI.

23. REFERENCES
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2009;59(1):5-11.
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2002;35(7):623-628.
•3. HOSOYA N, KURAYAMA H, IINO F, ARAI T. EFFECTS OF CALCIUM HYDROXIDE ON PHYSICAL AND SEALING
PROPERTIES OF CANAL SEALERS. INT ENDOD J 2004;37(3):178-184.
•4. GHABRAEI S, BOLHARI B, YAGHOOBNEJAD F, MERAJI N. EFFECT OF INTRA-CANAL CALCIUM HYDROXIDE
REMNANTS ON THE PUSH-OUT BOND STRENGTH OF TWO ENDODONTIC SEALERS. IRAN ENDOD J 2017;12(2):168-172.
•5. UZUNOGLU-ÖZYÜREK E, ERDOĞAN O, AKTEMUR TÜRKER S. EFFECT OF CALCIUM HYDROXIDE DRESSING ON THE
DENTINAL TUBULE PENETRATION OF 2 DIFFERENT ROOT CANAL SEALERS: A CONFOCAL LASER SCANNING MICROSCOPIC
STUDY. J ENDOD 2018;44(6):1018-1023.
•6. GRAZZIOTIN-SOARES R, DOURADO LG, GONCALVES BLL, ET AL. DENTIN MICROHARDNESS AND SEALER BOND
STRENGTH TO ROOT DENTIN ARE AFFECTED BY USING BIOACTIVE GLASSES AS INTRACANAL MEDICATION. MATERIALS (BASEL)
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